If you look into my repo and the particular commit(s) Jenkins had been able to create the 'blue-ocean-editor' branch in my initial commit (caused by the new BO pipeline) and also push the next commit "Expand my Blue Ocean pipeline", so I doubt that my Jenkins won't have the right credentials as discussed here.

However there are some timeouts. Not sure how much is this of concern.
Anyway, here's the full output of my BO pipeline:

I wonder what I could be doing wrong. I believe I have pretty much up-to-date Jenkins and all the plugins and OS, but briefly:
OS: Ubuntu Trusty 14.04.6 LTS
Jenkins: Jenkins ver. 2.161 (a bit behind, but I want to switch to the stable releases)
Plugins: Blue Ocean 1.13.2